Control some unused DO when using Impedance measure

[Blue21]

Hi

Analog Discovery 2 with impedance adapter.

I am trying to use the digital I/O (as output) that are not used by the impedance adapter 0-3 and 8-11. I mainly need 4 to control a front-end multiplexer for the impedance adapter. The adapter use I/O 4-7 and 12-15 as output.

As soon the Impedance measure is triggered, these I/O goes to zero.

Is there a way to control them or I need to use a second Discovery 2 to control the multiplexer and found some way to operate them in sync?

Thanks in advance for any suggestions.

[attila]

Hi @Blue21

The Impedance instrument with Adapter option uses the DigitalIO and Supplies device resource to control the IA Adapter relays.

To control the adapter and static io:
1. Select the Adapter option and Resistor value, press Run to take control and the resistor to be switched.
2. Select the first, "W1-C1-DUT-R-GND" option to release the DIO and Supply resources by the Impedance instrument.

Or a Script like this:

Impedance.Frequency.Setup.text = "Adapter"
Impedance.config()
Impedance.Frequency.Setup.value = 0

[Blue21]

Hi @attila 

Thanks for the quick answer.

If I understand well, there is not a real way to set the unused IO of the adapter (as output) and make a measurement using the impedance instrument and make that the set IO remain in their state. It is one or the other.

Actually I was able, using script to make link between 2 Discover2 (one for the impedance, one for the multiplexer):

use DIO0-3 to talk to the Discover2 with the mux and set channel
run impedance instrument and get measurement
next channel

This way the channel  is latched by the second Discovery2 attached to the mux. A little expensive solution for longterm.

Probably a hardware latch will be needed and powered by my multiplexer board.

Thanks in any case for the clarification.

Really amazing devices and especially the software. A little wish would be to have a line number indicator in the status line of the script source code. Would help to retrieve the line related to an exception.

[attila]

Hi @Blue21

In the next software version:
The SDK Impedance function (FDwfAnalogImpedanceReferenceSet) will only control the DIOs used by Adapter, leaving the others unchanged configured by FDwfDigitalIO functions.
In the WF application the unused DIOs with Adapter can be controlled under Options/DIOs or with Script.